1. Field of the Invention
This invention is related to a wrist and hand exercise device, and, more particularly, to such a device which can be used to freely exercise a user's wrist and help to align the carpal bones within the wrist to prevent or help alleviate Carpal Tunnel Syndrome effects.
2. Description of the Related Art
Carpal Tunnel Syndrome (CTS) is a widespread health problem, both in the United States and abroad. With the ever increasing use of computers and computer keyboards in virtually all fields of endeavor, the problem is getting worse all of the time. CTS is one of the leading causes of work related injuries and costs employers billions of dollars annually in lost production time and worker's compensation claims. CTS, and other musculoskeletal disorders were estimated by the U.S. Department of Labor Statistics (BLS) to account for over 60 percent of all work related injuries in the U.S. in 1995, not including back injuries. Furthermore, the number of cases of work related repeated trauma injuries has risen from 23,800 cases in 1972 to 332,000 cases in 1994, a fourteenfold increase. For cases involving days away from work, the BLS estimates that 32%, or 705,800 cases in 1994 were due to overexertion or repeated trauma injuries.
CTS is a repetitive motion injury which can be caused or aggravated by any repetitive flexing and extension action involving a person's wrists, such as, for example, typing or keyboard data entry. The underlying physical cause is the misalignment or fixation of one or more of the eight wrist "carpal" bones which surround the "carpal tunnel". Within this carpal tunnel nine flexor tendons, which control finger movement, and the median nerve, which is a pathway for sensory cells in the hand, pass through the wrist to the hand. When one or more of the carpal bones does not work harmoniously with the others, inflammation and swelling occur which can cause the carpal tunnel ligament to tighten down on the carpal tunnel and put pressure on the median nerve and/or the flexor tendons. A number of physical symptoms can accompany CTS, including pain, numbness, aching, burning and tingling sensations, stiffness, swelling, sensation of swelling where none exists, loss of strength and grip, and clumsiness. Symptoms may start in the hands and wrists and radiate upward to the forearm and shoulder joint. Severe CTS can result in atrophy of the thenar muscle at the base of the thumb and even in total hand and wrist disability.
Medical treatment of relatively mild CTS can include immobilization and rest, the use of ice packs to the affected area and drugs such as anti-inflammatories and diuretics to reduce swelling. Severe CTS is often treated with surgery, with approximately 100,000 operations per year occurring in the U.S. alone. Surgery is an expensive and risky procedure which is often unsuccessful. Full recovery from CTS surgery can take from months to a full year. Surgery can also lead to scarring of the transverse ligament within the wrist, which can further irritate the median nerve, thus causing CTS symptoms to reoccur.
Various therapeutic treatments have been developed for treatment of CTS without resort to surgery and drugs. One such treatment series, used most often by chiropractors, involves a product called the "CTD-Mark1 Pneumatic Traction Device" by ParaTech Industries, Inc. This machine, which costs several thousand dollars, includes a large console which is positioned near a sitting patient. The patient rests her elbow in an L shaped pad and a restraining strap is placed around her bicep while a second restraining strap is placed around her forearm. A third strap is placed around her wrist which third strap is attached to one end of a pair of nylon traction straps. The opposite ends of the nylon traction straps are attached to a rod extending upward out of the console. When operated, a pneumatic piston within the console urges the rod away from the L shaped pad, thus exerting force on the wrist brace in a linear direction, thus placing the patient's wrist into traction. According to the manufacturer's literature, "The resulting controlled extension of the arm and wrist causes a reduction in the compression of the carpal tunnel ligament upon the median nerve. The carpal bones now open to allow more room in the carpal tunnel as a result of the carpal ligament relaxation." Typically, 8-10 treatments are recommended for mild CTS while many more can be required for severe CTS. This can be a very expensive and time consuming experience, with each traction treatment involving a trip to the doctor's office (and accompanying payment).
In addition to the cost and attendant inconvenience of this complicated machine, the machine has some other problems. Since the patient's wrist is entirely immobilized when it is placed under traction, pressure is exerted in a given region of the wrist. However, CTS can be caused by misalignment or calcification of any one or more of the eight wrist bones surrounding the carpal tunnel. Pressure on the wrist in one orientation may be effective for one patient but ineffective for another. It is useful, therefore, for the wrist to be oriented in differing positions while undergoing pressure so that a variety of pressure points can be tried until the patient experiences alleviation of their particular CTS symptoms. With the CTD-MARK1, once the wrist is placed under pneumatic traction, the wrist cannot be turned, thus experimentation "on the fly" to find the best position for pain alleviation is difficult or impossible. Furthermore, the immobilization of the patient's elbow and forearm, and the rigid attachment of the wrist encircling strap to the nylon traction straps also does not permit much variation in traction pressure.
It is clear, then, that a better, and much less expensive wrist exercise and CTS treatment device and method is needed. Such an exercise and treatment device should preferably be inexpensive, yet safe and simple enough to use such that anyone exhibiting the symptoms of CTS can purchase and use the device in their own home without medical supervision. Such a device should allow a user to easily and effectively vary traction pressure on the affected wrist and wrist position in order to find the most effective wrist orientation for symptomatic relief from CTS.